The outburst from Iain Duncan Smith came as the UK’s highest court ruled the Government cannot trigger Article 50 without passing an Act of Parliament first.

It means both MPs and the unelected Lords will now be given a vote on whether the Government can begin the formal process of Britain’s divorce from the EU.

Unhappy with the decision, the Leave campaigner accused the judges of stepping into “new territory” as their decision would lead to “real constitutional issues”.

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Iain Duncan Smith blasted the judges for ruling agains the Government

Who is supreme – Parliament or a self-appointed court?

Iain Duncan Smith

“You’ve got to understand that, of course, there’s the European issue but there’s also the issue about who is supreme – Parliament or a self-appointed court?” The former work and pensions secretary told the Victoria Derbyshire programme.

With eight of the 11 judges ruling against the Government, the former Cabinet minister said he was “intrigued” the decision wasn’t unanimous.

He spoke of his upset of what he believed was unelected judges meddling with the running of a democratically elected Commons.

The Leave campaigner said judges were "telling Parliament how to run its business"

“I'm disappointed they've decided to tell Parliament how to run its business,” he continued.

“After all, there was a vote before in December overwhelmingly to trigger Article 50, so they've stepped into new territory where they've actually told Parliament not just that they should do something but actually what they should do.

“I think that leads further down the road to real constitutional issues about who is supreme in this role.”

The former Conservative leader’s remarks were challenged by fellow Tory and ardent Remainer Ken Clark.

He said the return of “Parliamentary democracy” should be welcomed – citing Mr Duncan Smith’s decision to rebel against his own party 11 times on the implementation of the Maastricht Treaty in British law.

“If you had lost this referendum you’d be behaving you did after Maastricht – now you’re saying the people have spoken,” Mr Clark blasted.

“But Ken,” Mr Duncan Smith responded. “You know very well in the way that Parliament works, the repeal of the ’72 European Communities Act will allow you to debate and amend anything you like on every element of this.”

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Continued cooperation with the EU to tackle terrorism and international crime.

Brexit Secretary David Davis confirmed on Tuesday the Government would table legislation to gain Parliament’s consent for Article 50 “within days”.

He told the Commons following the Supreme Court judgement: “This Government is determined to deliver on the decision taken by the people of the UK in the referendum granted to them by this House to leave the EU.

“So we will move swiftly to do just that. I can announce today that we will shortly introduce legislation allowing the Government to move ahead with invoking Article 50, which starts the formal process of withdrawing from the EU."